Caroline Coon is a morning person. When I arrive to interview her at midday, the artist, activist, and 'High Priestess of the Sixties Counterculture' has already been up for seven hours. In the Sixties, Coon would get up early to run Release, the help centre for people in trouble with the police over drugs, which she famously set up with Rufus Jones in 1967.

These days, Coon uses the early hours to paint, read or make agitprop fly-posters ('Purdah Murder'; 'Poverty Kills'). Until very recently, Coon also had to find time to immerse herself in law books, in order to be able to represent herself in her two-year legal battle with Random House, the company responsible for publishing Jonathon Green's 1998 book, All Dressed Up: the Sixties and the Counter-Culture .

In Green's book, a passage related how 'a young woman from Release' would give oral sex to rock stars in return for large donations. The book goes on to describe how George Harrison complied, while Mick Jagger accepted the sex, but sneered afterwards: 'If she thinks I'm going to give her a grand for a blow job, she's crazy.' It was all untrue.

Financially speaking, Coon was in no position to sue, but she did anyway. In June this year, she was awarded £73,000 in costs and damages (some of which she donated towards setting up an official Release archive), and All Dressed Up was withdrawn from sale.

'Defending myself was terrifying,' says Coon, as we sit in her pristine, bohemian west London living-room, surrounded by her colourful, sensual paintings. 'Technically, I hadn't done anything like it before so it felt like trying to drive a Ferrari down a coal mine.'

Coon reveals that one of the reasons she decided to take on Random House was the 'deeply misogynistic' reaction to her protest at the false allegations. 'I was told that although it was an untrue story, it was an amusing untrue story. I was lectured that if I hadn't prostituted myself for Release, then maybe I should have done, because it would have been a heroic act.' She smiles wryly. 'This was the reaction I was getting from what I could call unreconstructed Sixties Man.'

In Coon's opinion, it was a much more serious matter. 'To me, it amounted to verbal rape,' she says, calmly but emphatically, in her husky, genteel tones. 'It wasn't just this "funny" thing about a woman giving blow jobs to rock stars - it was one big pornographic humiliation fantasy. And there were racist elements to it, too. The paragraph before said something like, "Caroline Coon was upper class, but she slept with black boys which increased her exotic appeal".' Coon looks at me incredulously, and then lets out a short whoop of anguished laughter: 'And this is supposed to be 2000!'

Coon has had a lifetime of being misunderstood. Her provocative art has taken in a range of subjects including flowers, mythology, war and murder. However, she is mainly known for her work dealing in the diverse beauty of the human nude, in particular her studies of naked black men who also happened to be her friends and lovers. This has led to to Coon being referred to dismissively as 'the artist who likes to paint black men' or, even more bluntly, 'that woman who likes penises'.

Coon has long professed to be incensed by the double standards: 'Why is the penis hidden in culture? How many female nudes are there?' She was similarly amazed by the uproar in 1995, when the Liverpool Tate decided not use her painting, Mr Olympia, directly inspired by Manet's female nude, Olympia, because the black model had a semi-erection.

'I paint my life,' says Coon simply. 'My friends have always been multicultural.' Later, she says: 'What's wrong with painting penises? Journalists always come round and say [she adopts a sombre tone], "Caroline Coon is an artist who likes penises". But the idea that women will make love to men and not like the penis is to me psychopathic, pathological. We draw the penis into us; you have to love it. If you don't, then what is happening here?'

Coon herself is bisexual, though she prefers to keep that as quiet as possible for fear of titillating the general public. 'I try to be as private about my private life as I can be,' she says. 'But I still think it's very important to keep on discussing the theory of sexual liberation. My position is that I am not perverse at all. They are perverse. They are the bigots. They are the hypocrites. They are the ones in denial of their sexuality.'

Coon is sitting on the floor of her living-room, wearing dazzling white leggings and a matching top. The sun is streaming through the window and bouncing off her sleek hair, a mop of avant- garde, black-and-white stripes. At 55, her body is as taut, trim, and 'yoga-fit' as a woman half her age. While Coon has the courage of her sociopolitical convictions ('I consider myself part of a leftist project that wants change'), she acknowledges that her own situation is far from hellish.

'The world I live in, the heaven of Ladbroke Grove, means that any moan I might have about inequality is as nothing compared to what other people have to live through,' she says. Indeed, Coon cheerfully reveals that, in a rare bit of money luck, her heavenly west London home cost her only £15,000 because her Fenella Fielding accent got her on to some spurious, upper-income council list. 'Now that's what I call an interesting story about class,' she drawls mischievously.

Croline Coon was born in 1945 to a family of wealthy, ecologically conscious Kent landowners. It was an environment, Coon says, where women were regarded as little more than 'marriage-meat'. Influenced by this, she spent her youth loudly rejecting marriage, domesticity and motherhood, claiming, where the latter was concerned, that she 'wanted to be free to commit suicide'.

This decision starts looking even more complicated when you learn that Coon was sent away to board at the prestigious Legat Russian Ballet School at the age of five, mainly because her father abused her.

'I've had to say no to many men in life,' she says softly. 'And the first was my own father.' Although she had written passionately in the past on the subject of incest, Coon only went public about her own abuse very recently. However, reading past interviews, one is struck by how many times Coon hints at a terrible darkness in her background. It's as if, despite her best efforts, the secret she was keeping kept popping up into her mind like some sexually traumatic jack-in-the-box.

These days, Coon believes that her father was abused himself, and that she may have been sent to boarding school for her own protection.

Despite being severely dyslexic, she was happy at Legat, thriving in the disciplined, artistic, multicultural, 'gender-fluid' atmosphere. At 16, after a final row with her parents ('I wouldn't marry the next-door millionaire'), she decamped to London and her real life began in earnest. Along the way, Coon has dabbled in, among other things, modelling, movie-making, punditry and music journalism (during which she was the first to coin the term 'punk rock'). However, she is probably still best known for co-founding Release when she was still at art school.

Release helped everybody from homeless runaways to rock stars. At one point, the organisation was handling one-third of all drug busts in Britain. Coon attracted a lot of individual attention for a variety of reasons - her feminist mettle (she is one of Germaine Greer's dedicatees for The Female Eunuch) ; her feral beauty (she was known in London circles as 'Caroline Swoon'); and last, but not least, her unapologetic poshness and love of high culture.

She might have proudly marched alongside the newly politicised working classes in the Sixties, and been among the first to report on the likes of The Clash (whom she managed for a short period), but chez Coon, it was more about Anna Pavlova, Maria Callas and Stravinsky.

Then as now, Coon's main political beef was with sexual inequality. 'The idea that women are still perceived as second-rate is shocking,' she says disgustedly. 'People say this is a postfeminist age, but misogyny is still such a hot current in our culture. We need feminists in the vanguard more than ever.'

In the past, Coon's adversaries numbered other feminists who took exception to her appearance and behaviour. 'I was labelled decorative and beautiful and accused of being so just to attract men,' she recalls, 'whereas actually I didn't need to attract men. I was young! When you're young, you're up against the wall with offers.

'Women like me wanted love relationships without entering into the commercial exchange of marriage,' she continues. 'To our horror, we were called sluts, whores, easy lays, loose. It was so shocking that many women started going around, saying, "Oh no, I'm not an easy lay".'

In response to this, Coon famously put up a poster in her flat which read: 'Yes, yes, I'm an easy lay.' It was a protest against the then-prevalent belief that 'nice girls' had to be forced or tricked into sex, or they automatically ceased to be nice.

'Then as now, a lot of sex was just about playing out some sick rape scenario,' says Coon. 'It's all about men getting hard only as an aggressive act. It's a cheap, self-hating way for men to get hard and I'm not interested. It seems to me that men can get hard in a different, slower way. They can get hard by loving someone.

Well,' she finishes archly, 'that's the only "hard" I've ever been interested in.'

Coon resigned from Release in 1971, when the poverty, back-breaking work, sexist insults and inverted snobbery finally got too much. 'We're all performers, aren't we? I would never show it in public, but very often, I would just go home and weep.'

These days, people mainly seem to remember Coon for causing minor sensations, like wearing a transparent blouse for the Oz trial, putting red dye in the fountains at Trafalgar Square in protest at the Vietnam War, or getting herself jailed for a fortnight for brandishing fake spliffs at a demonstration. The irony of that last incident isn't lost on Coon. Despite her pro-drugs activism, she has never been into drugs herself, nor drink for that matter. For the interview, she graciously whips up some bucks fizz, but declares herself 'pissed' after one small glass.

It has to be said that, during the time I spend with her, Caroline Coon is extremely good company, fixing us lunch, breaking off in the middle of rants to relax into a little light gossip about sexist radioheads and chatting about art. Her favourite artists are Bridget Riley, Frida Kahlo and Georgia O'Keeffe, but she also has a lot of time for Rachel Whiteread and Tracey Emin.

'I think Tracey Emin is fantastic,' she says. 'I just hope she can cope with the vicious sexism with which she is now being interpreted. As an artist, I hold my breath for her.' As for Coon's own ongoing artistic-political-spiritual odyssey, she seems determined to regret nothing.

'There are times when I have to be tough, very tough, but I love it,' she says. A twinkle in her eye makes it easy to spot the brave, noisy young woman she once was, and in many ways still is. 'Oh, I don't think of myself as "mature" in any way,' smiles Caroline Coon. 'I think of myself as experienced.'

 Caroline Coon is trying to raise £25,000 to finance a professional archivist to work on the Release papers. Donations can be sent to the University Of Warwick Foundation, c/o Christine Woodland, University Of Warwick Library, Modern Records, Coventry, CB4 7AL

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